What the heck did I just see?! [video]

[itmo]

klingon ship on fire off the shoulder of orion? 

[RobertI]

There's a green thingy moving towards the red thingy....

[Lowen22]

chinese lantern?

[ollypenrice]

They can also be difficult to determine their distance and so can be closer then you think, therefore also appear move quicker.

This is the key point. If you over-estimate the distance you over-estimate the speed. I think it's a Chinese Lantern as well. 

Olly

[tingting44]

if i had to pick a UFO id go with Chinese Lantern...